An electrical connection device is widely used in various electronic information products and is used to connect different transmission ends to transmit signals. Due to the amount of data transmission is increasing and complicated, the electrical connection device needs to increase a transmission frequency and have more densely distributed transmission terminals to meet demands for a large amount of data transmission. However, a high frequency transmission is prone to face a problem of crosstalk due to the coupled signals between dense terminals, moreover, when the electrical connection device is engaged with an external transmission end (such as a motherboard) by a technology such as a surface-mount technology (SMT), most of the terminals are easy to produce a problem of poor coplanarity.
Chinese patent application No. CN2015105148029 (Chinese patent publication No. CN106469863A) discloses an electrical connection device which utilizes a plurality of signal terminals in a receptacle unit to connect the different transmission ends, and utilizes a grounding terminal interposed between the plurality of signal terminals to reduce a problem of a crosstalk between the signal terminals. Only when the electrical connection device has a plurality of receptacle units, the plurality of receptacle units are stacked with each other, the receptacle unit which is farther from the transmission end to be connected will require longer signal terminals to transmit the signals, for the longer signal terminals, an effect of reducing crosstalk by the grounding terminal interposed between the longer signal terminals is limited.
Additionally, an engagement of the terminal with a circuit board in the Chinese patent application is by that a pin-shaped tail portion of the terminal is inserted into a via on the circuit board, and the via would break the circuit board and reduce flexibility and freedom degree of a design of the circuit board. When the engagement of the terminals with the circuit board is replaced by an engagement through a technology such as the surface-mount technology to avoid the vias of the circuit board, the plurality of terminals will be easy to produce the problem of coplanarity, which is difficult to make the plurality of terminals coplanar and be reliably connected to the circuit board on correct positions.
The description in background as above merely is used to provide a background art, and it does not admit that the description on the background as above discloses the purpose of the present disclosure, and do not constitute a prior art of the present disclosure, and any description in background as above shall not be acted as any part of the present disclosure.